A simple ratiometric and colorimetric chemosensor for the selective detection of fluoride in DMSO buffered solution

A derivative of squaramide (cyclobuta[b]quinoxaline-1, 2(3H, 8H)-dione) has been synthesized for the ratiometric and colorimetric sensing of F- in aqueous solution in competitive fashion. With F-, probe 1 showed a highly selective naked-eye detectable color change along with a characteristic UV-Vis absorbance over other tested ions, which probably originates from the deprotonation occurred between 1 and F-, as proved by the H-1 NMR titration experiments and DFT calculations. (C) 2015 Elsevier B.V. All rights reserved.